Metal sheet drying oven



F. S. BAILEY METAL SHEET DRYING OVEN April 23, 1940.

Filed Feb. 4, 1939 ATTORNEY Patented Apr. 23, 1940 2,198,362 I METAL sneer name oven Frederick S. Bailey, Hoboken, N. J., assignor to National-Standard Company, a corporation of Michigan Application February 4, 1939, Serial No. 254,570

5 Claims.

This invention relates to an apparatus for drying freshly-coated, lacquered or varnished sheet metal plates, and the object of the invention is to provide means for efliciently drying the plates while the same are moved on a conveyor through a drying chamber or oven. J

More particularly, the invention contemplates the provision of a lengthy chamber or oven through which the plates to be dried are-carried on a conveyor; the provision of a plurality of air-circulating elements or fans arranged along at least one of the walls of the chamber near the floor thereof to direct air blasts toward the opposite side wall of the chamber where a plurality of heating elements or burners are located, with deflector. plates located between the fans and the burners. The invention also contemplates the provision of baiile plates by which the air blast of each fan is directed toward the deflector plates to concentrate the air blast thereon and to aid in the transverse circulation of heated air through the chamber between the plates to be dried.

In the accompanying drawing, wherein an embodiment of the invention is shown, Fig. 1 is a side elevation of the improved structure with certain portions thereof diagrammatically illustrated; Fig. 2 is a horizontal sectional view of a portion of the structure of Fig. 1; Fig. 3 is a sectional view on the line 3-3 of Fig. 1, looking in the direction of the arrows; and Figf' i is a sec; tional view on the line 4-4 of Fig. 1, looking in' the direction of the arrows.

The drying chamber or oven is in the form of a lengthy structure which may be composed of sheet metal 'or'other suitable materialand provided with a top or roof I, side walls 2, and a bottom or floor 3, the structure being supported in an elevated position upon supporting legs 3, or by any other suitable supporting means. The walls, top and bottom of the chamber are lined with an insulation or are otherwise suitably insulated. At one end, the chamber is open as indicated at 5, this end of the chamber comprising the entrance end-where the conveyor is loaded with the freshly coated plates, the entrance opening being provided with a hood or other pro.- tective device 6. Mounted to move through the chamber is an endless chain conveyor, which has its lower stretch I movable below the bottom or floor 3 of the chamber, and its upper stretch 8 movable through the chamber in a direction dried are supported on edge, so that the plates are carried through the chamber'by the conveyor in the manner well understood in this art, the dried. plates finally emerging out of the open exit end i l of the drying chamber and being suffi- Q ciently cool to permit their being lifted ofi the conveyor. The structure thus far described is well known in this art.

At the entrance end 5 of the chamber, a double walled enclosure I2 is provided, the spaces it be-- m tween the walls thereof forming passages or ducts through which vapors or fumes emanating from the varnished or coated plates which have just entered the chamber, may be drawn upwardly into the pipe M by means of the suction pump 3 I2 and exhausted therefrom through the pipe It to atmosphere. The inner wall l? of the chamber 92 is formed with a plurality of apertures l8 through which the vapors pass to enter the passages is as indicated by the arrows in Fig. 4.. a

As the plates are carried through the chamber on the upper stretch 8 of the conveyor they are carried past a plurality of air-circulating units which circulate air through the chamber and w around the plates, the air thus circulated being heated by suitable heating means In the form shown, each air-circulating unit comprises a fan 23 mounted in one of the walls 2 of the chamber near the bottom or floor 3 thereof and disposed to 30 direct a blast of air toward the opposite side wall of the chamber. Located directly opposite to each of the fans 23 is a deflector plate 26, secured tothe floor 3 and rising and curving upwardly therefrom and disposed directly in front of a gas burner 25 or similar heating device. As the fan directs an air blast toward the burner the upwardly curved, interposed deflector plate protects the gas flame from the blast, and the heated air is driven upwardly by the air blast 0 from the fan and is caused to circulate transversely of the chamber and around the coated plates being carried by the conveyor.

It will be noted that the fans, the burners and deflector plates therefore are arranged in 45 staggered relationship. That is to say, the burners along one of the side walls are spaced apart, with fans located in the spaces. b tween them and a similar arrangement is bad along the opposite wall, with the burners and deflector plates 50 so arranged that those along one wall face fans on the opposite wall. The staggered arrangement of the fans and the cooperating burners and deflector plates will be clearly apparent from Fig. 1. h u

0. 7 arranged to direct air blasts toward the deflectors A plurality of angular baiile plates 26 extend upwardly from the floor 3 of the chamber and are arranged transverselyof the chamber. Each-pair of baflle plates 25 extends divergently from one of the fans and acts to provide a widening air passage from each fan to the deflector plate against which that particular fan directs its air blast. By means of this arrangement of baflle plates disclosed, the direct intermingling of air blasts from the oppositely disposed fans does not take place until each air blast has impinged against the deflector plate toward which it is directed, and has been deflected thereby to rise above the baflie plates and there mingle with the heated air being circulated in similar manner by the several fans.

For desirable results it has been found useful to utilize the arrangement of divergent plates between the burners and within given areas in the chamber, namely, for a certain distance from the entrance end of the chamber and for a certain distance near the exit end of the chamber, leaving the intermediate portion of the chamber composed of fans ,'burners and deflector plates arranged as shown at the central portion of Fig. 2, or in other words; with the baffle plates omitted. Inthis central portion of the chamber a general transverse circulation of airwill occur, while near the entrance and exit ends of the chamber a concentration of heated air will result. Of course, it will be understood that almost any arrangement. of areas with or without the transverse baflie plates may be had according to various air-circulating arrangements desired, without departing from the spirit of the invention. v 1

' .Briefly,'the operation of the structureis as follows: I

The coated plates are placed on the conveyor 'either manually or by mechanical means.

As the plates are carried by the conveyor through the enclosure l2, the fumes and vapors arisingfrom the freshly-coated plates will be drawn through the apertures l8 in the inner wall I! and will pass out through the exhaust pipe Id. The conveyor thereafter successively carries the plates past the various fans 23, which with their associated burners, direct a continuous flow of heated air around the plates to dry the coating "thereon. Any or all of the burners may be controlled thermostatically, if desired, to regulate the heated air temperature in any selected section of the chamber. When the plates approach the exit end ll of thechamber, cooling means may be provided so that when they emerge from the exit end ll, they are suiflciently cooled to enable them to be,convenient lylifted from the conveyor.

What I claim is:

. ,1. An apparatus of the character described.

comprising, an elongated heating chamber having an entrance opening at one of its ends and an exit opening at its opposite end, a conveyor movable through the chamber from the entrance opening to the exit opening, a plurality of, bum- V are near the floor of the chamber and in spaced relationship, spaced fans near the opposite side walls of the chamber-at points between the burn- I ers, deflector plates located in front of the bumers, the fans at each side of the chamber being located at the opposite side of the her.

2.An apparatm of the character todirectairblastsacrossthechambertoward deiilector plates disposed in front of heating elements at the opposite side of thechamber, and.

baiile plates extending across the chamber and forming an air ww e between each fan and .the deflector plate at the opposite side of the chamber against wlnch'said fan directs an air 3. An apparatus of the 'ch aracter described comprising, a chamber through which a plurality of coated plates are transported for drying, a plurality of spaced fans disposed along one side wall of the chamber and arranged to. direct air blasts toward the-oppositeside wall, a plurality of, burners arranged along the. last-mentioned side wall in front of the fans, deflector plates located in ,front of the burners to receive the blasts from the fans, and a pair of baiiie plates extending transversely. across the chamber between afan and a deflector plate, the plates being disposed at opposite-sides of the fan at i one end and at the ends of the deflector plate at the other end, each pair of said plates diverging from .a fan toward a reflectorplate.

4. An apparatus of the character described comprising, a chamber through which a plurality of coated plates are transported for drying;

a plurality of spaced fans disposed along both side walls of the chamber, the fans on one side of the chamber being situated between those on the other side, all of the fans being arranged to direct air.blasts' to the side of-' the chamber opposite to that at which they are located, burners arranged along the side walls of the chamber between the fans, deflector plates in front of the burners, the deflector plates on each side of the chamber being disposed in front of the fans at the opposite side to receive air blasts therefrom, "and baiiieplatesextending across the chamber to form-an air passage betweeneach fan and 1 the deflector plate against which it directs an air blast.

5. A m apparatus of the characterdescribed comprising, a chamber through which a pluralityof coated plates are transported for drying,

said chamber having entrance and exit openings, a. plurality of spaced fans disposed along both side walls of the chamber, a plurality of spaced burners disposed along both side walls of the chamber, spaced deflector plates located in front of the burners, the fans at one side wall being located directly opposite to and directing air blasts against the deflector plates at the opposite side wall, bailie plates extending across the 'ehamberandformingpassage ways connecting each fan with the deflector plate against which.

said fan directs an air blast, said baiiie plates being'located adjacent fans situated near the entrance and exit FEEDERICK 

